Make `/cas` default for base CAS path

- `The base path on the CAS authentication server. ex: /cas` can be changed to `The base path on the CAS authentication server`
- `/cas` can be the default value of that field
- The dots should be removed from `The path where the user should be redirected to when logging in.`, `The path where the user should be redirected to when logging out.` and `The path that can be used to validate a ticket.`